Just when you thought Google was the Big Kahuna, a report comes out to challenge your assumptions. Like this one from BIGresearch which yields some new insights into which search engines have the most influence on buying decisions. Hint: It’s not Google.

The study looked at the influence of Internet advertising on purchase decisions and the findings may surprise you. Yahoo was ranked overall the #1 search engine choice for influencing purchase decisions and Google #4. I’m not terribly surprised that Yahoo! leads the pack here. Even though you can’t (and shouldn’t) sterotype searchers, I nonetheless tend to imagine the prototypical Google searcher as more savvy and research-oriented and the prototypical Yahoo! searcher as a ready buyer easily parted from his/her money. What does it say about the average Yahooer that one of the most popular search terms entered into Yahoo! is the word “google”? 😉 To the tune of 34,960,495 searches last month alone! This according to their Keyword Selector Tool. Can’t they figure out how to type google.com in the Location bar?

You also have to consider too that Yahoo puts the ads more in-your-face, so to speak, than Google.

Nonetheless, the rankings do move around once you start segmenting. Sometimes Google comes out in front — like in the Electronics sector. Here are some key sectors ranked in order of search engine preference:

Electronics
1. Google
2. Yahoo!
3. MSN
4. AOL
5. Ask Jeeves

Apparel/Clothing
1. Yahoo!
2. AOL
3. MSN
4. Google
5. Ask Jeeves

Car/Truck
1. MSN
2. Yahoo!
3. Google
4. Ask Jeeves
5. AOL

Grocery
1. AOL
2. Yahoo!
3. Ask Jeeves
4. MSN
5. Google

Hmm…. This might cause one to reassess his/her assumptions and priorities (and BUDGET) around paid search!

BIG hat tip to Shimon Sandler!